The present invention relates to fluid control apparatus for use in semiconductor manufacturing equipment, and more particularly to integrated fluid control apparatus which are so assembled that fluid control devices can be individually removed upward for maintenance and inspection.
As to the terms “front,” “rear,” “upper” and “lower” used herein, the right-hand side of FIGS. 1 to 3 is referred to as “front,” the left-hand side thereof as “rear,” and the upper and lower sides of FIG. 3 are referred to as “upper” and “lower,” respectively, and the terms “left” and “right” are used for the apparatus or the component thereof as it is seen from behind toward the front. The terms front, rear, upper and lower are used for the sake of convenience; the apparatus may be used with its front and rear portions positioned in opposite relation, or with the upper and lower sides thereof positioned as the left and right sides.
Fluid control apparatus for semiconductor manufacturing equipment comprise various fluid control devices as arranged in a plurality of rows, and the fluid control devices in adjacent rows have their channels interconnected by device connecting means at a predetermined location. Such fluid control apparatus are made integrated in recent years by connecting a mass flow controller and shut-off valves without using tubes. For example, Patent Literature 1 (the publication of JP-A NO. 2002-89798) discloses a fluid control apparatus comprising a plurality of lines arranged in parallel on a base plate and each comprising a plurality of fluid control devices arranged in an upper stage and a plurality of coupling members arranged in a lower stage, each of the lines having an inlet facing rearward and an outlet facing forward, the channels of specified lines being connected to one another by line interconnecting means.
FIG. 10 is a perspective view showing an example of fluid control apparatus disclosed in Patent Literature 1. The apparatus comprises as arranged in parallel on a base plate 1 three lines A1, A2, A3 having no bypass, and three lines B1, B2, B3 having a bypass. Each of the lines A1, A2, A3, as well as each of the lines B1, B2, B3, comprises a plurality of fluid control devices 2, 3, 4, 5, 6, 7 including a mass flow controller, shut-off valve and shutoff-opening device and arranged in an upper stage, and a plurality of coupling members 11, 12, 13, 14, 15, 16, 17, 40 arranged in a lower stage for interconnecting the fluid control devices 2, 3, 4, 5, 6, 7, 41.
The fluid control devices of each of the lines A1, A2, A3 having no bypass are the mass flow controller 2, inlet shut-off valve 3 connected via a filter 4 to the inlet side of the mass flow controller 2 and outlet shut-off valve 5 provided at the outlet side of the controller 2. The fluid control devices of each of the lines B1, B2, B3 having a bypass are the mass flow controller 2, inlet shutoff-opening device 6 connected via a filter 4 to the inlet side of the mass flow controller 2 and outlet shutoff-opening device 7 provided at the outlet side of the controller 2.
The inlet shutoff-opening device 6 comprises a body 21 in the form of a block, two shut-off valve actuators 22, 23 mounted on the body 21, a coupling 24 in the form of a block, having a tubular connector, and mounted on the top wall of the body 21, and a channel block 25 mounted on a side wall of the body. The outlet shutoff-opening device 7 comprises a first body (not shown) in the form of a block and disposed close to the mass flow controller 2, a first shut-off valve actuator 27 mounted on the first body, a second body 28 in the form of a block and disposed adjacent to the rear side of the first body, two shut-off valve actuators 29, 30 mounted on the second body 28, etc.
Provided in the fluid control apparatus are inverted U-shaped bypass pipes 35 extending above respective mass flow controllers 2. Each bypass pipe 35 has a tubular coupling 36 for making the pipe 35 separable into an inverted L-shaped portion and an I portion.
The mass flow controllers 2 and couplings 11, 12, 14 are attached to the base plate 1 by inverted U-shaped brackets 8, 9, 19. Each mass flow controller 2 is singly removable upward by removing couplings 15, 17 from opposite sides thereof. The filters 4 and the shut-off valves 3, 5 are individually removable upward by removing screws 37 driven in from above.
Indicated at 40 is a coupling in the form of a manifold block for connecting the three lines A1, A2, A3 having no bypass to one another although it is a single coupling. Indicated at 43 is a single coupling in the form of a manifold block for connecting the three lines B1, B2, B3 having a bypass to one another. Indicated at 41 are channel closing blocks attached to the coupling 40 with screws 37. Indicated at 42 is an inverted U-shaped bracket for attaching the couplings 40, 43 to the base 1. The manifold block coupling 40 is connected to the manifold block coupling 43 by a communication pipe 44. These couplings have a common outlet which is provided by the terminal end of the coupling 43. A shut-off valve 45 having a tubular coupling 46 is provided at this end.
The bypass-equipped lines B1, B2, B3 are so interconnected that the block couplings 24 of the inlet shutoff-opening devices 6 thereof are connected to one another, and block couplings 33, each having a second tubular connector, of the outlet shutoff-opening devices 7 are connected to one another, respectively by inverted U-shaped communication pipes 47, 48 serving as line interconnecting means. An L-shaped coupling L and a T-shaped coupling T are used for each of these line interconnecting means 47, 48, and these coupling L, T are joined to the pipe P by welding (as indicated at W in the drawing).
In the case of the fluid control apparatus disclosed in Patent Literature 1, each line has block couplings arranged in the lower stage and removably attached to a base plate, each fluid control device in the upper stage is removably mounted on two block couplings in the lower stage, and the fluid control devices of each line are made easy to remove and mount individually. However, since the line interconnecting means comprises couplings which are welded to a pipe for connection, the apparatus has the problem of necessitating time and labor for interconnecting the lines and disconnecting the lines from one another when lines are to be added or the arrangement of lines is to be altered.
To solve this problem, Patent Literature 2 (the publication of JP-A No. 2004-183771) discloses a fluid control apparatus comprising a plurality of lines arranged in parallel on a base plate and each comprising a plurality of fluid control devices arranged in an upper stage and a plurality of coupling members arranged in a lower stage, each of the lines having an inlet facing rearward and an outlet facing forward, the channels of specified lines being connected to one another by line interconnecting means, the fluid control apparatus being characterized in that the line interconnecting means comprises lower channel blocks arranged respectively in the upper stages of the specified lines to be connected in the same position with respect to the front-to-rear direction and each provided with a line interconnecting channel having at least one upward opening, and one or a plurality of upper channel blocks arranged over the lines to be connected on the upper side of the lower channel block and each having a lateral channel extending orthogonal to the lines and a downward channel extending from the lateral channel and communicating with the upward opening of the line interconnecting channel of the lower channel block, the lower channel blocks being removably fastened to the lower stage channel members with screws from above, the upper channel blocks being removably fastened to the lower channel blocks with screws from above.
The fluid control apparatus of Patent Literature 2 has the advantage of eliminating welded portions from the line interconnecting means and being amenable to the addition or modification of lines, but has the problem of being increased in the number of kinds of channel blocks, and still remains to be improved.